Galectin-3 CRD Expression and Purification

The galectin-3 CRD (Gal3C; amino acid residues 113−250) was expressed and purified as either a thioredoxin fusion construct(25 (link)) or isolated Gal3C. The expression protocol was identical for the two constructs and has been reported elsewhere.(25 (link)) The purification protocol for isolated Gal3C was very similar to that reported previously,^{25 (link),64 (link)} except that the final steps including and following cleavage were omitted. ¹⁵N/¹³C/²H-labeled Gal3C was expressed in 60% D₂O using published protocols.(65 (link)) To obtain stereospecific methyl assignments, one culture was grown on a mixture of 10% uniformly ¹³C-labeled and 90% unlabeled glucose.(66 (link)) Typical yields of isolated Gal3C were 100−150 mg/L of culture.